package com.itheima.reggie.controller;


import com.itheima.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;

@RestController
@RequestMapping("/common")
@Slf4j
public class CommonController {
    @Value("${reggie.path}")
    private String basePath;

    /**
     * 文件上传
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public R<String> update(MultipartFile file){

        // 1). 获取文件的原始文件名, 通过原始文件名获取文件后缀
        String originalFilename = file.getOriginalFilename();
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));

        // 2). 通过UUID重新声明文件名, 文件名称重复造成文件覆盖
        String fileName = UUID.randomUUID().toString()+suffix;
        // 3). 创建文件存放目录
        File dir =new File(basePath);
        if(!dir.exists()){
            dir.mkdirs();
        }
        try{
            // 4). 将上传的临时文件转存到指定位置
            file.transferTo(new File(basePath+fileName));
        }catch(IOException e){
            e.printStackTrace();
        }

        return R.success(fileName);
    }

    /**
     * 文件下载
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response){
        try {
            //输入流，通过输入流读取文件内容
            FileInputStream fileInputStream = new FileInputStream(new File(basePath + name));

            //输出流，通过输出流将文件写回浏览器
            ServletOutputStream outputStream = response.getOutputStream();

            response.setContentType("image/jpeg");

            int len = 0;
            byte[] bytes = new byte[1024];
            while ((len = fileInputStream.read(bytes)) != -1){
                outputStream.write(bytes,0,len);
                outputStream.flush();
            }

            //关闭资源
            outputStream.close();
            fileInputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
